Interesting. Although I tend to agree, it's worth considering one possible difference between cutlery and computing devices: cutlery may have very little usage overlap, and computing devices may have considerable usage overlap.<p>I actually use my notebook and tablet for reading (even the same content!), I actually use all devices for facebook, I actually use my phone and tablet for gaming, and so forth.<p>For some tasks, one device type is clearly superior to all others (notebook for typing, tablet for sketching). For many tasks though, clear superiority is hard to establish, or is heavily context dependent.<p>Ultimately, Steve had it right - for the iPad to succeed, it had to be clearly better for some important things. Strong separation of uses is not required.
The iPad is succeeding because of a 10 hour battery life with wireless and a capacitance screen with an easy to use on screen keyboard. It was like Microsoft's Oragami project but worked for under $500. Android tablets can't beat it because now that platform has to duplicate the ease of use at the same price point, something which it has been unable to do.